Low Coolant Light Is On... But I'm Full

[firesice18]

In my 2004 Saturn VUE Redline my low coolant light is on but I have topped off the coolant overfill so I know it is not low on coolant. Also, the motor does not run hot at all so I know there is circulation throughout the system. Has anyone else ever had any issues with the sensor going bad? Also, where is the sensor located? On the bottle itself? Any help would be greatly appreciated.

[Someclown]

The sensor is in the bottom of the purge tank(bottle) and may be of the float and magnet type.If this is the case the magnet may have come detached and on the bottom of the tank causing a low coolant light

[RobertGary1]

If you reach down in the tank you can probably move the float with a screwdriver. Check to ensure the float is not stuck and pull it up with a screwdriver. Its most likely stuck as the electronics to determine float position are pretty reliable.

-Robert

[Mgg4591]

I don't know if this applies to the vue but I'll tell you anyway. I had the low coolant light come on in my sl2. The coolant was full and I cleaned out the tank to make sure the float wasn't stuck. I previously noticed that my reverse lights were out and later found out that the coolant sensor and reverse lights were on the same fuse.

The fuse was blown, I replaced it and I got my reverse lights back and the coolant light went off.

[murrayd6]

Hey firesice18, I also have an 04 Redline Vue and my low coolant light just started coming on intermitently despite the reservoir being full. Did you ever find a solution that resolved your problem?

[mrtube]

I hope you guys don't literally have the tank "full" It should be around the center rib of the tank when hot.


When we bought our 06 vue last year someone had filled the tank alll the way up with green antifreeze. within a few days I drained the system, flushed it out really good and refilled with 50\50 mix of dex.

Altho having the tank actually full shouldn't damage anything and won't trigger a light it will blow the crap out if it has to. and that can be messy.

[far2grumpy]

Originally Posted by murrayd6

Hey firesice18, I also have an 04 Redline Vue and my low coolant light just started coming on intermittently despite the reservoir being full. Did you ever find a solution that resolved your problem?

murrayd6 ... refer to post 4 regarding the SL2 backup lamps and coolant level circuit using same 10 amp fuse. This is also true for the Vue - with fuse in under-hood fuse box.

I doubt if a fuse would cause an intermittent light - unless there's a bit of corrosion ... but it'd be simple to check.

The coolant circuit is basic - I've attached the schematic.

The switch or float type is not clear based on schematic ... why don't you let us know what you find.

[nvrdieyng]

My wife has a 2004 Vue that had teh light going on and off. She told me the battery light was on. Sure enough when I drove it, it looked like a batery light was on, so I had the alternator replaced for $175 today! As I left the light came on, and I walked in to have the mechanic look at it. He smiled at me and said, "That's not a battery pictire, thats your radiator! The Alternator light is up on top!" So now that I feel like a jackass, I can go replace the switch under teh coolant reservior and it will hopefully work fine! The alternator was old anyway I guess!!!

[BarefootRose]

Eek! My low coolant light came on yesterday --was on when I started the car. I thought it was the battery light until I looked it up last night. But here's the thing: it stayed on about 5 minutes, then went off for the rest of the drive (another half-hour). When I came home, the same thing happened.

The low coolant light has never flashed on before, even on engine startup (which the manual says is normal.) If it stayed on, I'd know it's freak-out time, especially as I had the coolant system repaired just 2months ago because of a leak. But it goes off.

Haven't checked the reservoir yet--but I will later today, when I can face it.

Anybody else have and solve this problem?

(Btw, the gas tank sensor goes on alot and randomly--the people who sold me the car said the float's worn out, so I just keep track of milage with the odometer. Could this be a similar issue?)

[far2grumpy]

Check reservoir for adequate fluid level (mid-tank seam). If fluid is ok the fluid level switch is probably sticking. I've had success using homemade "swisher" to clean the tank switch ... I'll post a picture wheen I get back to my pc.

[far2grumpy]

Thumbnail is my home-made swisher to clean the low coolant level switch.

I started with typical coolant temp test tool and added about 12 inches of 3/8 ID plastic tubing (fish tank supplies).

Remove expansion tank pressure cap - insert tool - squeeze and release bulb to fill with coolant and position the hose near center of bottom of expansion tank.

Give several good shots of coolant in general direction of switch - remove tool - install pressure cap and check results.

I used on 06 Vue with about 95K miles and problem has not returned at 140K miles. However, I did have coolant changed when timing belt and water pump were changed around 100K miles.

Generally speaking the cooling system should be drained, flushed and refilled with Dex-Cool at 5 year intervals (or 150,000 miles). A sticky switch is probably early reminder a fluid refresh is needed.

[Speedyox]

Thanks Far2Grumpy.

I couldn't remember if I had a coolant gauge and it's too cold to search very long so I stuffed some 3/16 ID hose on plastic glue bottle and got the same effect. My coolant light is off now after being intermittent and then steady on for a few days.

My coolant light started coming on and and off intermittently last week and so I topped up the coolant. Then it came on the next day and I thought I had a leak until I found that the level was still fine. It steadily got worse for a few days until yesterday when it was on [probably] constantly.

Hopefully it's "fixed" now.

[bermany]

Originally Posted by firesice18

In my 2004 Saturn VUE Redline my low coolant light is on but I have topped off the coolant overfill so I know it is not low on coolant. Also, the motor does not run hot at all so I know there is circulation throughout the system. Has anyone else ever had any issues with the sensor going bad? Also, where is the sensor located? On the bottle itself? Any help would be greatly appreciated.

I know this is an old thread. But I have been plagued with this bright light shining in my face for four years. And hope to help out any Google searches, like I searched. To turn off this light, supply 12v to the green wire going to the sensor.
Done deal.